[Heath] LMO rebuilding....did I mess it up?

Mon Mar 14 04:47:08 EDT 2016

Hi Guy

Simple solution, just slacken the LMO tuning capacitor shaft to the worm  
gear, rotate it 180 degrees and retighten.

73

Bob

Bob F Burns G3OOU,  G-QRP 6907, @BobFBurns
Crystal Palace Radio & Electronics Club: _www.g3oou.co.uk_ 
(http://www.g3oou.co.uk/) 
Technical web site: _www.qsl.net/g3oou  

In a message dated 13/03/2016 23:49:04 GMT Standard Time, gggdds at js-net.com 
 writes:

It is working; it tunes 5.0 to 5.5mhz as tested with  my counter.....only 
problem is that 5.0nhz is at the full counterclockwise  position of the 
shaft--I set it up backwards!!
Guy

On 3/13/2016 3:29 PM, 

_ (http://www.qsl.net/g3oou) _G3OOU at aol.com_ (mailto:G3OOU at aol.com) _ wrote:
_ (http://www.qsl.net/g3oou) 
Hi Guy

I would check the frequency of the LMO output with a frequency counter  
before doing anything else. It should tune from 5.5 - 5MHz plus a small  
overlap i.e. it tunes from high to low when the SB101 tunes from low to  high.

73

Bob
Bob F  Burns G3OOU, G-QRP 6907, @BobFBurns
Crystal Palace Radio &  Electronics Club: 

_www.g3oou.co.uk_ (http://www.g3oou.co.uk/)  (http://www.qsl.net/g3oou) 
Technical web site: _www.qsl.net/g3oou  

_ (http://www.qsl.net/g3oou) _ 
In a message dated 13/03/2016 18:26:02 GMT Standard Time,  
gggdds at js-net.com writes:
_ (http://www.qsl.net/g3oou) 

Glen,  and any other members  of the Heathkit listserve,

I think I have a problem, and it's not  in Houston....I got the 80 band 
tuned up on my SB-101, so I thought I'd  try it on the air..I found an 80 meter 
LSB group of hams talking ,and  having tuned up the 101' into a dummy load, 
I turned it onto the antenna  and called...they came right back and said I 
had a nice signal...no  tuner...I asked "what frequency are you showing?" 
and he came back  "3900khz".   Only one problem...I was tuned to 3691khz!!  I  
checked this again on 40 meters...same thing...when I transmit a signal  
using my Elecraft K2 on 7400khz, the 101' is reading (and receiving) it on  
7181khz...Did I do something wrong with the LMO?  I checked it's  range of 
movement,and with the tuning unit dialed all the way  counterclockwise, the  
variable cap is almost closed; then, five  turns to the right and the cap is 
fully opened, as I recall.  I  didn't check it on any other bands, but at the 
moment, it would seem the  LMO's output is 219khz t_oo low....right?   It's 
reading 219khz low  exactly on both bands..... Help....

A bit of history.  I know  virtually nothing about the history of this 
101'....I bought this one,  with another 101' and two HP23 series power supplies 
from a nearby ham for  $100.  He had bought them from another ham, hoping 
to get one working  one out of the pair.  He never had time to delve into 
either of  them....

Guy
WA6OQQ,
On of the hams at Heath

On 2/1/2016 1:40 PM, Glen Zook  wrote:

_ (http://www.qsl.net/g3oou) 
 (http://www.qsl.net/g3oou) _
The LMO can be removed without  removing the front panel.  You do have to 
loosen the setscrew on  the dial assembly, unsolder the wires to the LMO, and 
remove the 4-nuts  on the underside of the chassis.

Remove the main tuning knob and  loosen the large nut on the panel that 
holds the shaft.  Move the  shaft so that the slip drive is removed from the 
dial.  Then, lift  the LMO from the chassis and away from the dial.

After making the repairs,  put the LMO back in place and reverse the 
directions.

Glen,  K9STH 

_ (http://www.qsl.net/g3oou) _Website: _ (http://www.qsl.net/g3oou) 
_http://k9sth.net_ (http://k9sth.net/)  (http://www.qsl.net/g3oou) 

 (http://www.qsl.net/g3oou)  (http://www.qsl.net/g3oou) 
 (http://www.qsl.net/g3oou)  
 (http://www.qsl.net/g3oou)  
_  
____________________________________
 From: Guy Giacopuzzi  _ (http://www.qsl.net/g3oou) _<gggdds at js-net.com>_ 
(mailto:gggdds at js-net.com)  (http://www.qsl.net/g3oou) _
To: Glen Zook _ (http://www.qsl.net/g3oou) _<gzook at yahoo.com>_ 
(mailto:gzook at yahoo.com)  (http://www.qsl.net/g3oou) _ 
Sent: Monday, February 1, 2016 2:22  PM
Subject: Re: LMO  rebuilding....
_ (http://www.qsl.net/g3oou)  (http://www.qsl.net/g3oou) 

Glen,
Thanks for  your help....I followed some of your advice, and the advice 
that I  didn't follow came back to bite me.....I acquired a couple of SB-101's  
for a song (well, a song plus $100, but it included two power  
supplies....)....and I've been "bringing the 1st one 'back'" so to  say....cleaning, 
checking, going thru the tune up routine, etc......I  rebuilt the LMO on an 
SB-101....removed the front panel, etc to get to  it...had to do a lot of 
general cleaning as the entire dial assy was all  gummed up.   I took apart and 
cleaned the LMO...lubed it,  removed and cleaned the stops, but I didn't do 
the braid  thing......I used a high end light oil for the lube...from  
Kroil....I got it on the air last night, loaded it into a 75 ft long  wire w/ no 
tuner and joined a group at about 3800kc or so but they kept  reporting I was 
"jumping all over the place"...as I listened, I heard  them, but the 
frequency kept changing...or "warbling" as you say. My  signal was plenty 
powerful, and the group was spread _out all over the  California coast up past San 
Francisco...so the 6146B's were really  kicking, so to say.  So, I reread 
your email and this time,  downloaded the file on LMO rebuilding.  I'm going to 
attempt  removal of the LMO w/o removing the front panel--can I do that?   
Maybe I'll have to remove the "escutcheon"  to set the dial on  
right...Anyway, now I think I've got to do the braid....I was going to  use a bit of 
"soldering" or maybe I should say "de-soldering" braid...Is  that ok?   Anyway, 
I should have followed all of your  advice, not just some of it.  One other 
interesting thing....when I  tuned in the stations, my RF gain control 
didn't work, and when I looked  at it, the diode on the middle terminal had let 
go...but wow, did the  receiver have a lot of gain.  When I hooked it back 
up, the  gain seemed to back down a bit.  I thought I'd play with that just  
a bit to see if the control is somehow hurting the overall receiver  gain...

_ (http://www.qsl.net/g3oou)  (http://www.qsl.net/g3oou) _
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